Anchoring structure for building slabs



March 29, 1960 f E. R. HAMILTON ETAL 2,930,220

ANCHORING STRUCTURE FOR BUILDING SLABS Filed May 31, 1955 (//l//l//l/ United States Patent-O i" AN CHORING STRUCTURE FOR BUILDING SLABS Edward R. Hamilton, Austin, Tex., and Carl T. Fomstrom, Pacific Palisades, Calif., assgnors to United States Lift Slab Corporation, Austin, Tex., a corporation of Delaware Application May 31, 1955, Serial No. 512,266

s claims. (ci. 121)' In a copending application bearing Serial No. 179,024,

filed August 12, 1950, now U.S. Patent 2,758,467, issued August 14, 1956, ,there is described a building method and apparatus wherein ceiling or roof slabs of a building are formed or poured at one level and then raised to another level. Normally, a base or foundation slab is poured first with vertical columns set therein as described in U.S. Letters Patent No. 2,686,420, issued August 17, 1954. An upper lioor, roof or ceiling slab is then poured at ground level on top of the foundation slab and around the vertical columns which are to support the slabs.

'I'hese columns or some of them, carry at their upper ends suitable lifting means, the latter being connected to the slab to be raised by lifting or tension rods. The slabs are normally cast from concrete or some similar material requiring reinforcement at the points where the lifting process imposes considerable stress. Thus, collars are vcast into the slab in slidable engagement with the vertical columns, such collars serving the combined purpose vof reinforcing thel concrete providing means of fastening the slab to the columns when the slab has been raised to the proper position providing an eicient securement of `the tension rods to the slab and providing a protective collar between the slab and the columns.

FIt :has heretofore been the practice in carrying out the method set forth in the aforementioned patent and the said copending application to attach the supporting blocks, brackets or the like as by welding to the columns after thel slab to be anchored to the columns has been raised toanappointed level. And, as suggested by Patent No. 2,686,420, to provide blocks between the collars and the proximal faces of the columns.

'Such procedures of applying supporting brackets or the like to the vertical surfaces of the columns where the operators must work on scaffolding, ladders and the like, ismost'diflicult, time-consuming and expensive. In accordance with the principles of the instant inventionv therefore, such di'iculties and hazards are eliminated by placement of the aforementionedabutments upon the columns before the same are raised to the vertical posi tion, and the collars, as well as the wedges for anchoring the ,collars to the columns are modified accordingly.

`In anearly Patent No. 1,066,436, issued July 1, 1913, there is suggested the principle of insertion of sectional brackets or shoulders between the slab and outturned flanges at the median ends of the column sections. The suggestions of this patent are unsatisfactory however, because collars are not maintained in sliding engagement with the columns and, therefore, are unsupported during the raising operation, because the sectional Ybrackets fail to compensate for irregularities in the distances between the slabs and the flanges, and because of several other factors hereinafter to be made clear.

IIt is the most important object of the instant invention, therefore, tov provide anchoring structure for build-A ing slabs that is safe not only during the lifting operations, but while the slab is being anchored to the columns and throughout the life of the building employing the same.

Another important object of this invention is to pro- I vide anchor means which is easily and quickly applied,

thereby eliminating the expense, loss of time and danger incident to methods heretofore employed in this field.

A further object of this invention is to provide -apparatus that. is strong, durable and fully capable of anchoring` the slab to Ilthe columns without danger of displacement.

A still further object of the invention is to provide means for making minor height adjustment of the slab v at a particular column by placing of the securing wedges between abutments on a column and the collar of the slab.

Qther objects include important details of construction,`

allof which will be made clear as the folowing specificationprogresses, reference being had to the accompany-` ing drawing wherein:

Figure 1 is a cross-sectional view through a vertical column showing a slab broken away to illustrate one of its collars in plan and illustrating anchoring structure made pursuant to the present invention.

Fig. 2 is a fragmentary, cross-sectional view taken on linelII-,II ofFig. l; and

Fig. 3 is a cross-sectional view similar to Fig. 2 showing another embodiment of the instant invention.

Except for certain important details of construction td be hereinafter set forth, the particular nature of the collar employed in connection with the anchor structure illustrated in the drawing, is of no consequence and, therefore, there is shown a collar broadly designated by the numeral 10 and having the same general characteristics as that disclosed in a copending application Serial No. 305,722, filed August 22, 1952, now abandoned.

It consists of a base plate or ange 12 which normally lies in the plane of the bottom 14 of a concrete slab 16 within which the collars 10 are cast, but in some cases the plate 12 may advantageously be positioned above the lowermost surface 14 of the slab 16. Plate 12 is joined to, or forms a part of, a sleeve 18 at the lowermost edge of the latter and in order to provide additional strength, a number of structural supports or gussets 20 may be placed around the outer surface of the sleeve 18 and the upper face of the plate 12.

A pair of outwardly extending tubes 22, preferably formed integrally with the plate 12 and with the sleeve 18, are provided with keyhole slots 24 which receive tension or lifting rods,(not shown) provided with heads that are received within the tubular elements 22. It may be pointed out that vsuch lifting rods depend from' lifting jacks supported at the uppermost end of each vertical column 26 respectively in much the same manner as disclosed in Patent 2,686,420, wherein but one lifting screw is employed for each column respectively. As the jacks are simultaneously actuated, the slab 16 is raised along the plurality of vertical columns 26` as'thecollars 10, and particularly vthe sleeves 1S, slide along the coumns 26.

The lifting apparatus and method set forth in application Serial No.V 179,024 above-mentioned, forms no part of the instant invention and, therefore, reference may be had to Patent No. 2,686,420 for a general understanding gonal in transverse cross-section, the shape thereof is of f Patented Mar. 29, 1960 gescreen- 18 are provided' with a clearance opening? 32 for eachabutment 28 respectively.

After'the slab 161is raised to its appointedlevel above' the abutments 28, and while" the slab being supportel' by each of the jacks at the uppermost endsoff the eolu'mns through useof"`the aforementionedlifting rods connected within the tubular elements\22,,mernbers" 34'- are-l insert'ed or driven into' place betweentheldwertnost.faceL offthecollar and-the.uppermost'"endsa of* theabutnientsn 28; Inasmuchas the column26 andthe'sleeve 18-are each provided with four sides, th'ere is illustrated afplu-i rality ofabutmentsl on each of'the fur faces ofi-'the column 26 and accordingly, four merE1bers`-34 will b'efem ployed inthe manner shown' in'-Figs. land 2`ofthed`rawing.

The members 28 and 34"are in the naturefofco-acting wedges by virtue of the fact'that the lovverrnost edge! 36"'V of the `members 34"are inclinedand the uppermostv ends 38 of the abutments 28 likewise slope'downwardly toward one'corner of the column26. The* uppermost edges 40 of the wedges 34 bear'flatlyl against the lowermost fa'ce ofi thecollar 10 however, andby virtue'ofsuch construetion there is provided a tight lit forl the` wedges lilbe-` tween the abutments 2S and the collars 10 lwhetherv ornot theslab 1'6 is in a truly horizontal-position atlthe time of anchoring the same tothe columns 26. By these wedges'l 34acting on the abutrnents 28 and on-the collars thereis:

provided a minor height adjustment for the slab.` This isL an important feature in making-minor level adjustments ofl the slab 14.

Itis to be noted that thewedges 34 traversethe=lower-;

most open ends of the clearance passages'or openings 32' and in order to avoid any possibility of displacement of the Wedges 34-from the wedge-like' abutments 28, the"Y collar 10 is provided with grooves 42 in thelowermostface thereof for receiving the uppermost edges 40 offthe" corresponding wedges-34; While the edges 40 and the co-operating grooves 42 areV illustrated in Fig; 2 as Vf shaped, the contour thereof may be varied asl desired;

While it is absolutely essential that the sleeves IS'remain in substantial sliding engagement with the columns 26' from a safety standpoint throughout the time the slabs 16 are lifted from the ground level to the point of anchoring, slight clearance must be provided as seen in Fig. 1 to allow for imperfections in dimensions and therefore, in order to eliminate any lateral movement ofthe slab 16 relative to the columns 26, the passages 32 should be filled with grout or other material, and in this respect it is to be preferred that a pair of coacting Wedges 44 and 46 be driven into place within each passage 32 respectively in tight engagement not only with the faces-of the columns 26, but with the sleeves 18.

Another manner of accomplishing the desired result is illustrated in the embodiment of Fig. 3 of the-drawing and wherein Wedges 234 are heldl against lateral displacement through the medium of' extensions or flanges 242- depending from the collar 210 in overlapping relationship to the outermost faces of the wedgemembers234;

Whilebut one: column 26 has been illustrated in the drawing,` it is toV be understood of course,` that thesame' anchoring structure is to be employed'for each-ofthe plurality of i columns utilizedin supporting the series of..

superimposed slabs 16 forming the various floor levels -7g;

ofthe finished building. Each slab 16 is provided with' a collar cast therewithin for each column 26 respectively and, therefore, when the relatively large number of anchoring structures hereinabove described are utilized for each slab respectively, there isl no possibility whatsoever of accidental displacement or sagging and all'haard's, as well as aggravating time and expense in attaching the slabs to the columns are eliminatedl through employment ofthe principles hereinabove set forth.

It is now clear also that the above-described improvements solve' the problem of attachment ofthe slabs to concrete columns since it is but necessary to mount the abutments 28 on cross members traversing the concrete columns and embedded therein.

Having thus' described the invention what is claimed as-new and desired to be secured by Letters Patent is:4

1`. In abuilding structure the combination comprising;

a'vertical support column having an abutmentthereon andA a gradualV inclined upper surface extending; generally` tangentially to aside surface portion of'said column, al"- slab, a collar embedded' in thehorizontal slab, said collar slidableV into position along said column and over said? abutment thereon, and a support inthe form of a wedge member inserted between said inclined surface. onsaid` abutment and said collar to transfer the load ofl said sla-b at said column through said embedded collar to said` abutment, said wedge member when moved cooperating. with said abutment surface and said collar to permit-4 rninor height adjustments of said collarand slab with respect to said abutment along said column.

2. In a building structurethe combination accordingto claim l wherein said collar has a horizontal bottom,V

face above said inclined surface on the abutment and said. wedge member positioned between said collar and;V

abutment has ahorizontaltop surface and an; inclined lower surface of like incline to said incline on the. abutment, saidiwedge member acting as a wedge to eleet minor adjustments in height of said collar and slab and' to transmit the load of said slabat the column through said collar to. said inclined surface on said abutment.. e

3. In a building structure the combination according.

to claim 2 wherein said collar above said abutmentformed with a groove and said wedge member has an upper projecting edge received` in said groove whereby said support member is locked in place.

4. In a buildingstructure the combination according to claim 2 wherein said collar above saidwedge memberL has an olset flange depending inspaced relation to saidA column, said depending ange portion extending down--` wardly alongside the outside of the upper portion off said wedge member and holding said wedge member in place 5l In a building structure the combination according` to claim 2 wherein said collar is also formed'witli a second vertically extending recess open on one side adjacent said column, saidf second recess receiving a pair of vel-v` tically extending and cooperating wedge members drivabl against each other to form a tight fit between oolumnand collar.

References Cited inthe le of this patent UNITED STATES PATENTS 

